全文获取类型
收费全文 | 132篇 |
免费 | 0篇 |
专业分类
化学 | 89篇 |
晶体学 | 1篇 |
力学 | 4篇 |
数学 | 4篇 |
物理学 | 34篇 |
出版年
2021年 | 2篇 |
2020年 | 1篇 |
2019年 | 1篇 |
2018年 | 2篇 |
2017年 | 1篇 |
2016年 | 5篇 |
2015年 | 2篇 |
2014年 | 4篇 |
2013年 | 6篇 |
2012年 | 9篇 |
2011年 | 10篇 |
2010年 | 13篇 |
2009年 | 12篇 |
2008年 | 4篇 |
2007年 | 6篇 |
2006年 | 8篇 |
2005年 | 3篇 |
2004年 | 5篇 |
2003年 | 4篇 |
2002年 | 3篇 |
2001年 | 6篇 |
2000年 | 4篇 |
1999年 | 4篇 |
1998年 | 2篇 |
1996年 | 3篇 |
1995年 | 2篇 |
1994年 | 2篇 |
1993年 | 2篇 |
1992年 | 1篇 |
1990年 | 1篇 |
1989年 | 1篇 |
1986年 | 1篇 |
1982年 | 1篇 |
1980年 | 1篇 |
排序方式: 共有132条查询结果,搜索用时 31 毫秒
11.
12.
13.
A modification of the simple theory of rotation-dependent anisotropy is applied to the analysis of f.c.c. crystals, in both constrained and unconstrained multiple-slip orientations, with the object of resolving the question of uniqueness of solution. Specifically, tensile loading in each of 4-, 6- and 8-fold symmetry and [110] loading in channel die compression for each of [
10] and [00
] lateral constraint are investigated. It is established that the modified simple theory, augmented by the postulate of minimum plastic work, uniquely predicts equal multiple-slip and lattice stability (relative to the force axis or axes) in all cases. 相似文献
14.
The dynamics of biphotonic intensity holographic gratings (BIHGs) based on dye-doped liquid crystal (DDLC) films, including optical and thermal effects, are studied. Experimental results indicate that the formation of a BIHG involves bulk reorientation and surface adsorption. The former yields a transient biphotonic grating; the latter results in a persistent biphotonic grating. Additionally, the dynamic behaviours of the biphotonic diffraction signals are different from those of a conventional one-photonic diffraction signal, and depend on the intensity(polarization) of the green(red) pump-beam. The effect of ambient temperature on the diffraction efficiency of a BIHG is also studied: a higher ambient temperature prevents more dye molecules from being adsorbed on the substrate. 相似文献
15.
Hai Du Ru-Chun Amy Fuh Junzhong Li L. Andrew Corkan Jonathan S. Lindsey 《Photochemistry and photobiology》1998,68(2):141-142
A database of absorption and fluorescence spectra, including molar absorption coefficients and fluorescence quantum yields, has been compiled for 125 photochemically relevant compounds. An accompanying program enables calculation of oscillator strengths, natural radiative lifetimes, transition dipole moments, Forster energy-transfer rates, multicomponent analysis, simulations of fluorescence spectra upon energy transfer among linear arrays of pigments, calculations of blackbody radiator curves at different temperatures and Lorentzian and Gaussian peak distributions. The program runs under Windows 95 and is equipped with extensive literature references and help features. 相似文献
16.
M.-S. Li S.-Y. Huang S.-T. Wu H.-C. Lin A. Y.-G. Fuh 《Applied physics. B, Lasers and optics》2010,101(1-2):245-252
Two-dimensional (2-D) square lattice (SL) photonic crystals (PCs) are fabricated, and their optical/electro-optical properties are studied. The PCs are based on polymer-dispersed liquid crystals (PDLC) that are formed using two-beam interference with double exposures. The PC structure that is observed using a scanning electron microscope matches with the calculated interference pattern. The results of optical/electro-optical studies demonstrate that superprism and negative refraction effects occur at certain incident angles over a range of frequencies and are consistent with the simulated ones. Moreover, the negative refraction efficiency is electrically controllable. 相似文献
17.
The induced optical aberration of laser beam passing through a transparent flowing fluid layer on a metal specimen is experimentally and empirical formula studied. The proposed study presents an experimental investigation of metal surface roughness measurement by combining an optical probe of laser-scattering phenomena and adaptive optics (AO) for aberration correction. In the absence of the AO correction scheme, induced flow velocity of 0.278 m/s can severely degrade the residual wavefront root mean square (RMS) error to 0.58 μm and decrease the scattered laser intensity. Real-time AO correction in closed-loop at a sampling rate of 8Hz can reduce the wavefront RMS error to 0.19 μm and improve the attenuation of scattered laser intensity. The maximum relative error of the estimated roughness (R a) is less than 7.8% compared with the stylus method. The experimental results show satisfactory correction in the presence of a flowing fluid layer using the AO system. 相似文献
18.
19.
Shuo-En Tsai Wan-Ping Yen Ching-Chun Tseng Jia-Jun Xie Ming Yu Liou Yi-Ting Li Naoto Uramaru Fung Fuh Wong 《Tetrahedron》2018,74(22):2787-2791
The efficient acid catalytic synthesis of pyrazolo [3,4-d]pyrimidine was developed by treating 1H-pyrazol-5-yl-N,N-dimethylformamidine with various aminating agents including N,O-bis(trimethylsilyl)hydroxylamine (NHSiMe3(OSiMe3)), cyanamide (NH2CN), hydroxylamine (NH2OH), methoxyamine (NH2OMe), hydrazine (NH2NH2), and urea (NH2C(O)NH2) in acidic solution at reflux. Based on the experimental result, cyanamide (NH2CN) and methanesulfonic acid were indicated the best aminating agent and acid mediated solvent. On the other hands, the reactivity tendency was involved the activity of original leaving species grafting on the aminating agents, such as –OH, –OMe, –OSiMe3, –NH2, –OSiMe3, –C(O)NH2, and –CN, in acid catalytic heterocyclic reaction. 相似文献
20.
An efficient and facile procedure for the preparation of 1-[2-(6,7-dimethyl-3,4-dihydronaphthalen-2-yl)ethyl]pyrrolidine hydrochloride
from 6,7-dimethyl-1,2,3,4-tetrahydronaphtalen-1-one in four steps is proposed. It includes one-step synthesis of 1-(6,7-dimethyl-1,2,3,4-tetrahydronaphthalen-2-yl)acetic
acid as key intermediate and subsequent transformations of functional groups therein.
Published in Russian in Zhurnal Organicheskoi Khimii, 2008, Vol. 44, No. 3, pp. 449–453.
The text was submitted by the authors in English. 相似文献